1. Field of the Invention
Embodiments of the present disclosure relate to liquid crystal display technology, and more particularly to a light guiding system, an edge type backlight module and a liquid crystal device.
2. Discussion of the Related Art
LEDs or fluorescent lamps are usually adopted as backlight sources TFT-LCDs. Both of the light sources are driven by electrical power. As the power consumptions of the backlight source may be over eighty percents of the total amount of the power consumptions, it may be accumulated to a huge amount after a long period of time. Currently, oil-fired, coal-fired, or nuclear electricity are major power generation methods, which may result in environmental problems such as greenhouse effect, nuclear pollution, and so on.
Ambient lights, such as sun lights, are natural resources not harmful to environment. The ambient light includes visible lights needed by the backlight sources, and thus the ambient light may be collected and be propagated into backlight modules by light guiding devices. In this way, the ambient light may be utilized as backlight sources so as to reduce the power consumption.
FIG. 1 is a schematic show of a light guiding system of a typical edge type backlight module. The light guiding system 1 absorbs ambient light CL via an ambient light collection system 10 and generates absorbed light SL. The absorbed lights SL are guided into a plurality of optical fibers 20. Light emitting ends 21 of each of the optical fibers 20 are arranged close to a light incident surface 31 of a light guiding plate 30. The lights emitted from the light emitting ends 21 enter the light guiding plate 30 via the light incident surface 31. The lights are then mixed within the light guiding plate 30 and emit out via a light emitting surface 33. In this way, lights emitted from the light emitting ends 21 can be the backlight source of the backlight module 1.
The main problem of the above backlight module structure resides in that the emitting angle of the light emitting ends 21 of the optical fibers 20 is small than 60 degrees. When the light emitting ends 21 of the plurality of optical fibers 20 are close to the light incident surface 31 of the light guiding plate 30, the brightness difference shown on the light incident surface 31 may be obvious if a gap between two adjacent light emitting ends 21 is larger. The gap may be reduced by arranging more optical fibers 20. However, the cost and the manufacturing complexity are increased with such solution.